Molluscicides have gained a great attention in recent years and proved to be a good way of snail
control. C. limon was tested as a molluscicide against adult Biomophalaria alexandrina snails
and a larvicide against Schistosoma mansoni larvae (miracidia and cercariae). Lethal
concentrations, LC50 and LC90 values were detected for both tests (744.17 and 1821.25 ppm,
respectively). B. alexandrina snails, non-infected and infected with S. mansoni were exposed to
Citrus limon peel extract concentration of 150 ppm for 4 weeks compared to non expoed with C.
limon and/or infected controls. The meracidea, cercariae, egg production, protein electrophoresis
and DNA fragmentation analysis and organ histology of B. alexandrina were assessed. C. limon
exposure stimulated the growth rate, increased the number of eggs/snail/week (59.31 ± 5.71),
inhibited reproductive rate by 20.6 %, hatchability rate (57.7 %) and stimulation of cercarial
production. Histological investigation of C. limon extract exhibited necrosis and deformation of
hermaphrodite and digestive glands of infected and non-infected B. alexandrina snails. C. limon
exposure led to increase in total protein intensity of the hermaphrodite-digestive glands in both
exposed/exposed-infected snails. RNA intensity was increased in C. limon exposed and
exposed-infected snails during the experimental period. Necrotic DNA form was a characteristic
of C. limon and/or infection.